Patent Literature 1 proposes an information display system that displays contents displayed on a display unit of a portable information terminal on a display unit of an in-vehicle apparatus.
In this information display system, a control unit included in the portable information terminal also supplies information displayed on the display unit of the portable information terminal to the in-vehicle apparatus through an interface. Furthermore, the control unit of the portable information terminal supplies manipulation command data of the portable information terminal to the in-vehicle apparatus through the interface. Thereby, the manipulation command of the portable information terminal is displayed on the display unit of the in-vehicle apparatus; the in-vehicle apparatus also functions as a manipulation part of the portable information terminal.